[request] Not exactly an ST port.... Black Tiger Redux?

[lmimmfn]

Originally Posted by chadderack

The thing about this is discovering any pattern.

Some of the data structures have function pointers embedded in them.

I just found the orange dragon (level 6?) and there's a ton of frames and information. Each dragon seems to have two entire tile blocks to itself. 2 of the 8 that are used for sprites are just the three dragons (Level 3, Level 6, Level 8) (with the different palettes). One quarter of the sprite tiles are dragon!

It's quite possible that the structure layout for each game is different (and even each sprite).

Have patience; we're going to get to the higher-level language brick by brick

No no, take your time man we're just discussing amongst ourselves, as said i can help with transformation tools no problem if needed.

[chadderack]

Originally Posted by lmimmfn

No no, take your time man we're just discussing amongst ourselves, as said i can help with transformation tools no problem if needed.

Cool

Well, I can kinda try to give an idea of what I'm doing here (briefly).

I have MAME running Black Tiger, which I have put into the test screens.

1) Run MAME debug (mame.exe -debug blktiger)
2) in the debug window console, type bp 1b4

3) Hit f5

4) When the breakpoint at $1b4 is hit, type pc=1ac in the debug window console and hit enter

5) Hit Alt+Enter to make the game screen into a window and resize it somewhat small

6) Hit F5. You're in the test screen




In order to get to the screens I'm using to identify sprites, you have to simulate the service buttons. The mame service button does not work in debug; but you can use a key sequence to get through the screens.

7) press both the "1" and "2" keys on your keyboard at the same time (not on the numeric keypad... the normal "1" and "2" keys.

This combo cycles you through the various test screens. Press it twice and you'll get to a screen like this. The object test, which is the sprite test.



This view of the sprite test can be useful, as it puts a tile index next to each piece of a sprite. I find the combined view to be more useful.

8) Click the left CTRL button and the sprites will come together.



There's still a sprite index along the top and sides...

(continued)

[chadderack]

The left and right keys on your keyboard control the palette and whether or not the sprite tiles are flipped. Hit the left key and your palette cycles up to 7



If you go past a palette value of 7, you get to 8 (which is the same palette as 0 only the tile is flipped horizontally)

So if we want the same color as palette 3 but flipped, cycle to object test 0B



Anyway... if we want to find sprites in the code, we use the two index values.

The first one comes from the table... (below) the second comes from the object test number (which is the sprite attr)

EX: 03 0b would be the upper left tile of this character:



Black Tiger's code refers to sprites like this... by the upper left index of the sprite... and then the code extrapolates the rest (add 1 to the tile number for the second tile, add 7 to get one row down, add 1 for the bottom right tile for a sprite that is 2x2 tiles... like the player sprite).

If you want to look for sprites other than the main character, hit the left ALT button. This takes you to the next page of sprites. Seems that in Black Tiger, only every other "page" has sprite tiles.

Since I want to look for the Orc character, I'll hit the button 4 times to get an object test of 40:


Now I want the ORC, so I use the up and down arrow keys to look through the sprite page...



That palette looks wrong, so use the left arrow key to get to the brown orc


Anyway... knowing this, you can look through the source code for these codes. Just find a character in the sprite object test, find the tile number and sprite attr number and do a search.

I want to see if the brown orc (facing left) is in the code, so I search for "80 45" in the source code. Lo and behold, I find it. Now I can start figuring out what the sequence in the code does... (cont'd at some point)

[saimon69]

I Have the idea that tiles are flipped via software to save RAM so you might not find right oriented characters

[chadderack]

Originally Posted by saimon69

I Have the idea that tiles are flipped via software to save RAM so you might not find right oriented characters

It would seem that way; but it's not. I'm finding both left and right-flipped sequences separately for all characters. Seems they could have coded it like that, but did not.

Here's an example... one of the brown orcs walks back and forth. Notice that the sprite attribute goes from 45 to 4D (45 | 0x8)... meaning that the character turned around.



So far in code I've found references to the player, the goblins (purple/orange), the Orcs (brown so far only), the skeletons (including skull throwing), the orange dragon, the pots with prizes in them, holes in the wall with prizes and a few others. There's something to find each time.

[saimon69]

Just checking the pulse of the project ^^ By the way i did not found Black Tiger to be supported by Hoot but maybe someone can prove me wrong - and the VGM player option (with all those command line) is so darn alien to me - i need to dust off my lua

[chadderack]

Just checking the pulse of the project ^^

Still going well... much more data defined now. Found pretty much all enemies and entities (except for the knives the player throws).

Found a lot of the data around the old man who sells you things. I'd forgotten that they had misspelled "Skull" as "Scull"

I've found all the functions that set up all the enemies as well as the different versions of the old man

                             OLD_MAN_ACTIONS_JMP_TBL                         XREF[1]:     ram:5fc7(*)  
        ram:5fcd dd 5f           dw         OldManAwardsPlayer100PointsAndZenny
        ram:5fcf 08 60           dw         OldManOpensShopToPlayer
        ram:5fd1 25 60           dw         OldManAwardsPlayerMoreVitality
        ram:5fd3 4b 60           dw         OldManAwardsPlayerMoreTime
        ram:5fd5 78 60           dw         OldManGivesAdviceSpinningScull
        ram:5fd7 97 60           dw         OldManGivesPlayerGratitude
        ram:5fd9 a8 60           dw         OldManGivesAdviceSeekHiddenSymbols
        ram:5fdb 08 60           dw         OldManOpensShopToPlayer

;ETC...

                             PURCHASE_SELECTION_JUMP_TABLE                   XREF[1]:     CheckPlayerMakesPurchaseSelectio
        ram:6660 fe 67           dw         CheckPlayerMakesPurchaseSelection::Maybe_BuyBu   row 1 col 5
        ram:6662 78 66           dw         Maybe_PurchaseItemTopRow01
        ram:6664 7c 66           dw         Maybe_PurchaseItemTopRow02
        ram:6666 80 66           dw         Maybe_PurchaseItemTopRow03
        ram:6668 84 66           dw         Maybe_PurchaseItemTopRow04
        ram:666a e0 66           dw         Maybe_PurchaseItemBottomRow01
        ram:666c e4 66           dw         Maybe_PurchaseItemBottomRow02
        ram:666e e8 66           dw         Maybe_PurchaseItemBottomRow03
        ram:6670 ec 66           dw         Maybe_PurchaseItemBottomRow04
        ram:6672 4c 67           dw         PurchaseKeyFor30Zenny
        ram:6674 87 67           dw         PurchasePotionFor150Zenny
        ram:6676 0a 68           dw         CheckPlayerMakesPurchaseSelection::maybe_remov

...and found some screen elements this morning (just placed them on the test screen to identify what they were...)

[chadderack]

And now after a little more work... you see how the pseudo "code" is transformed:

                             PURCHASE_SELECTION_JUMP_TABLE                   XREF[1]:     CheckPlayerMakesPurchaseSelectio
        ram:6660 fe 67           dw         CheckPlayerMakesPurchaseSelection::update_time   row 1 col 5
        ram:6662 78 66           dw         PurchaseWeaponLevel01
        ram:6664 7c 66           dw         PurchaseWeaponLevel02
        ram:6666 80 66           dw         PurchaseWeaponLevel03
        ram:6668 84 66           dw         PurchaseWeaponLevel04
        ram:666a e0 66           dw         PurchaseArmorLevel01
        ram:666c e4 66           dw         PurchaseArmorLevel02
        ram:666e e8 66           dw         PurchaseArmorLevel03
        ram:6670 ec 66           dw         PurchaseArmorLevel04
        ram:6672 4c 67           dw         PurchaseKeyFor30Zenny
        ram:6674 87 67           dw         PurchasePotionFor150Zenny
        ram:6676 0a 68           dw         CheckPlayerMakesPurchaseSelection::time_to_sho

I found the code that Xs out the selections a player can't make in the shop.

[chadderack]

Anyone wanting to follow along or try their hand at Ghidra... I just put the project on GitHub. I won't be accepting pull requests for now, but you can check it out if you like.

https://github.com/admiral68/gh_black_tiger

[chadderack]

A lot of good progress.

Finding vertical blank code as well as the way that Black Tiger does delays. That stuff was sort of tricky to work out; but it will help figure out a whole lot more of the game.

It seems like I'm always finding things I'm not looking for. I started looking for how the game managed when a player is poisoned, and ended up finding a ton of other unrelated stuff first.

To recap--I am attempting to reverse engineer Black Tiger to discover what amounts to a high-level flow chart of the game rules.

If I had to guess, I'd say there's still probably a couple more weeks of this before we get to anything resembling a "flow chart" for all of Black Tiger's game rules... probably longer than that.

Any work directly on the Amiga will not probably happen for about a month (at best).

[dlfrsilver]

Originally Posted by chadderack

A lot of good progress.

Finding vertical blank code as well as the way that Black Tiger does delays. That stuff was sort of tricky to work out; but it will help figure out a whole lot more of the game.

It seems like I'm always finding things I'm not looking for. I started looking for how the game managed when a player is poisoned, and ended up finding a ton of other unrelated stuff first.

To recap--I am attempting to reverse engineer Black Tiger to discover what amounts to a high-level flow chart of the game rules.

If I had to guess, I'd say there's still probably a couple more weeks of this before we get to anything resembling a "flow chart" for all of Black Tiger's game rules... probably longer than that.

Any work directly on the Amiga will not probably happen for about a month (at best).

Take the time, there's no hurry

[saimon69]

I anticipate will go for three channels tunes because i tried in the past to do some Black tiger music in two and tose for purists might not sound too good, unless otherwise requested

Usually for ease of access purpose i try to put together interactions in the same mod file so for each level we might have:


main tune
dungeon tune
boss tune
store tune
game over

Then despite will probably need to recreate instruments using Deflemask as much as i can do and use around maybe 200k for all the chords, will have purists telling me is NOT identical to the arcade, darn -_- is ok if i replace with dark metal sepultura style for an alternative soundtrack??? :P

[chadderack]

Originally Posted by saimon69

Then despite will probably need to recreate instruments using Deflemask as much as i can do and use around maybe 200k for all the chords, will have purists telling me is NOT identical to the arcade, darn -_- is ok if i replace with dark metal sepultura style for an alternative soundtrack??? :P

Why not have a Black Tiger Amiga port fork version that does nothing but dark metal sepultura style

If you want to dig into the Yamaha synthesis code, the relevant MAME code (in C/C++) is in these files:

https://github.com/mamedev/mame/blob.../sound/ymopn.h
https://github.com/mamedev/mame/blob...mfm/src/ymfm.h
https://github.com/mamedev/mame/blob.../src/ymfm_fm.h
https://github.com/mamedev/mame/blob...src/ymfm_opn.h
https://github.com/mamedev/mame/blob...c/ymfm_adpcm.h
https://github.com/mamedev/mame/blob...nd/ymfm_mame.h
https://github.com/mamedev/mame/blob...src/ymfm_ssg.h
https://github.com/mamedev/mame/blob...c/ymfm_ssg.cpp

At some point I was going to build a version of MAME just to debug the sound synthesis engine. In Black Tiger there are 64 unique sounds/music, not including the blank/stop sounds

Here are some notes if you want to start on the Sound ROM:

//snippets of code mixed with other stuff

//LOCATIONS OF VARIOUS SOUNDS ON THE SOUND ROM:
                             SOUNDS_TABLE                                    XREF[1]:     Maybe_PlaySoundEffect:020e(*)
        ram:0dc1 00 ff           dw         FF00h                                            Sound 0: FF stops music playing
        ram:0dc3 49 0e           dw         PLAYER_LOSES_VITALITY_SOUND                      = 8Fh
        ram:0dc5 9e 0e           dw         PLAYER_DEATH_SOUND                               = 8Fh
        ram:0dc7 7f 0f           dw         ENEMY_INJURED_BLOOP_SOUND                        = CFh
        ram:0dc9 d4 0f           dw         ENEMY_DEFEATED_SOUND                             = CFh
        ram:0dcb fe 0f           dw         ITEM_TAKEN_SOUND                                 = 88h
        ram:0dcd 7b 10           dw         PLAYER_TAKES_ZENNY_COIN_SOUND                    = 88h
        ram:0dcf f5 10           dw         FIRE_PILLAR_WARNING_SOUND                        = 88h
        ram:0dd1 5e 11           dw         POT_BREAKS_REVEALS_COIN_SOUND                    = C8h
        ram:0dd3 c7 11           dw         FIRE_PILLAR_SOUND                                = C8h
        ram:0dd5 08 12           dw         GAS_JET_SOUND                            = C8h
        ram:0dd7 32 12           dw         WEAPON_CLASH_METALLIC_BATTLE_SOUND               = 88h
        ram:0dd9 84 12           dw         KILL_BAT_SOUND                                   = C8h
        ram:0ddb ae 12           dw         PLAYER_EARNS_EXTRA_LIFE_SOUND                    = 8Fh
        ram:0ddd 64 13           dw         POT_BREAKS_SOUND                                 = 88h
        ram:0ddf bc 13           dw         PLAYER_DISCOVERS_TREASURE_SOUND                  = C8h
        ram:0de1 86 14           dw         BIG_BOSS_HIT_SOUND                               10
        ram:0de3 b0 14           dw         TIME_EXPIRING_SOUND                              = 81h
        ram:0de5 ee 14           dw         PLAYER_GETS_ITEM_FROM_OLD_MAN_SOUND              = 88h
        ram:0de7 cc 15           dw         BOOM_EXPLOSION_SOUND                             = C8h
        ram:0de9 0d 16           dw         UNKNOWN_ALARM_SOUND                              = 81h
        ram:0deb 4e 16           dw         IMPACT_SOUND                                     = C8h
        ram:0ded 78 16           dw         CLASH_SPINNING_COIN_SOUND                        = C8h
        ram:0def a2 16           dw         PLAYER_LOSES_ARMOR_SOUND                         = 8Fh
        ram:0df1 08 17           dw         MICHELIN_MAN_FIREBREATHING_SOUND                 = C8h
        ram:0df3 35 17           dw         FIRETHROWER_TAUNT_SOUND                          = C8h
        ram:0df5 b2 17           dw         PLAYER_CLIMB_SOUND                               = 88h
        ram:0df7 c8 17           dw         FLAIL_EMPTY_HIT_SOUND                            = 88h
        ram:0df9 de 17           dw         PLAYER_LANDS_ON_PLATFORM_SOUND                   = 88h
        ram:0dfb 1c 18           dw         PLAYER_ASCENDS_DURING_CUTSCENE_SOUND             = 88h
        ram:0dfd 32 18           dw         PLAYER_GRABS_LADDER_SOUND                        = 88h
        ram:0dff 01 ff           dw         FF01h                                            1f: stops playing music
        ram:0e01 10 1b           dw         COIN_OR_CREDIT_ADDED_SOUND                       = 4Fh    O
        ram:0e03 8c 1b           dw         LEVEL_1_MUSIC                                    Level 1 music
        ram:0e05 de 1f           dw         LEVEL_2_MUSIC                                    = 06h
        ram:0e07 ef 23           dw         LEVEL_3_MUSIC                                    = 06h
        ram:0e09 b7 27           dw         LEVEL_4_MUSIC                                    = 06h
        ram:0e0b 27 2d           dw         LEVEL_5_MUSIC                                    = 06h
        ram:0e0d 07 32           dw         LEVEL_6_MUSIC                                    = 06h
        ram:0e0f c4 35           dw         LEVEL_7_MUSIC                                    = 06h
        ram:0e11 7c 3a           dw         LEVEL_8_MUSIC                                    Level 8 music
        ram:0e13 cb 3f           dw         BOSS_MUSIC_01                                    = 06h
        ram:0e15 f5 41           dw         FIGHT_DRAGON_MUSIC_01                            = 06h
        ram:0e17 8b 44           dw         FIGHT_DRAGON_MUSIC_02                            = 06h
        ram:0e19 70 47           dw         OLD_MAN_SHOP_MUSIC                               = 06h
        ram:0e1b 7e 49           dw         DUNGEON_MUSIC_01                                 = 06h
        ram:0e1d 96 4b           dw         ENTER_INITIALS_MUSIC                             = 06h
        ram:0e1f 9d 51           dw         AFTER_ENTER_INITIALS_MUSIC                       = 06h
        ram:0e21 82 52           dw         INTRO_MUSIC                                      30
        ram:0e23 48 54           dw         GAME_OVER_MUSIC                                  = 06h
        ram:0e25 13 55           dw         SUCCESSFULLY_FINISH_LEVEL_MUSIC                  = 06h
        ram:0e27 fa 55           dw         FINISH_LEVEL_8_MUSIC                             = 06h
        ram:0e29 a4 5e           dw         CONTINUE_MUSIC                                   = 06h
        ram:0e2b 51 60           dw         MAYBE_PERFECT_BONUS_MUSIC                        = 06h
        ram:0e2d d2 60           dw         UNKNOWN_FANFARE_MUSIC                            = 06h
        ram:0e2f 6d 61           dw         UNKNOWN_FANFARE_MUSIC_02                         = 06h
        ram:0e31 04 ff           dw         FF04h                                            38 stops music playing
        ram:0e33 36 62           dw         UNKNOWN_FANFARE_MUSIC_03                         = 06h
        ram:0e35 5c 18           dw         FLAIL_HIT_SOUND                                  = 88h
        ram:0e37 86 18           dw         FALLING_SOUND                                    = C1h
        ram:0e39 9c 18           dw         BOUNCING_SOUND_(LOOPS)                           = C1h
        ram:0e3b c9 18           dw         OLD_MAN_TALKING_SOUND                            = C8h
        ram:0e3d 57 19           dw         OLD_MAN_TALKING_SOUND_02                         = C8h
        ram:0e3f a9 19           dw         DRAGON_DIE_SOUND                                 = 90h
        ram:0e41 90 1a           dw         MAYBE_BLOCK_BOUNCE_UP_SOUND                      40
        ram:0e43 ba 1a           dw         FALLING_SOUND_02                                 = C8h
        ram:0e45 d0 1a           dw         BOSS_HIT_SOUND                                   = C8h
        ram:0e47 e6 1a           dw         DRAGON_SPEW_FIRE_SOUND                           43 might be the last sound


//*********************************************************
//  YM2203 DEVICE
//*********************************************************

DEFINE_DEVICE_TYPE(YM2203, ym2203_device, "ym2203", "YM2203 OPN")

//-------------------------------------------------
//  ym2203_device - constructor
//-------------------------------------------------

ym2203_device::ym2203_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) :
    ymfm_ssg_device_base<ymfm::ym2203>(mconfig, tag, owner, clock, YM2203)
{
}


//-------------------------------------------------
//  device_start - start of emulation
//-------------------------------------------------

void ym2203_device::device_start()
{
    // set our target output fidelity
    m_chip.set_fidelity(SSG_FIDELITY);

    // call our parent
    parent::device_start();
}

[saimon69]

My C skills are darn low -_-

If the ROM was supported by hoot i would simply have channels muted one at the time and record to wav file so to import the sample in milkytracker and adapt it

However i was just ranting because have several remakes of soundtrack going on and not sure any of those projects will be terminated by the dev (like Robocop in example) - and those take a discrete time to make
[ Show youtube player ]
for what concerns alternate soundtrack, i can do good stuff if left full freedom!
[ Show youtube player ]
Have someone tell me they dislike funk on a game music but this for me is bringing the 70s Martial arts movie feeling!

[chadderack]

Originally Posted by saimon69

i was just ranting because have several remakes of soundtrack going on and not sure any of those projects will be terminated by the dev (like Robocop in example) - and those take a discrete time to make
[ Show youtube player ]

I'm not familiar with Robocop or I could have a better opinion, but the tracker seems to be playing good music. Nice work!

I think for any development project, creating tools might be important. For something high level like

"Black Tiger Music Sounds" => "Amiga port"

you kind of have to create a high level abstraction of what you need to do.

If it were me, this is how I'd approach it:

1) Rip YM2203 data from sound rom
2) Interpret YM2203 data: find instruments, etc...
3) Put each sound/song into an intermediate format
4) Translate that intermediate format into something protracker can play on the Amiga hardware

Seeing those high level tasks, I believe creating a tool to do the first two jobs would be ideal... maybe the first three.

I'm a C#/Java (really anything) developer, so I can quickly create a utility app that will do those three jobs.

With the sound data in an intermediate format, it can be re-input into ProTracker format.

The reason I favor sound synthesis instead of using WAVs is that WAVs (on the Amiga, at least) take up huge amounts of room. Sound synthesis takes up relatively little, and we have the Paula chip to do it for us. (Paula, right? Not Agnes or Denise? )

Dealing with storage/loading issues will be a separate problem to solve

[saimon69]

Originally Posted by chadderack

I'm not familiar with Robocop or I could have a better opinion, but the tracker seems to be playing good music. Nice work!

I think for any development project, creating tools might be important. For something high level like

"Black Tiger Music Sounds" => "Amiga port"

you kind of have to create a high level abstraction of what you need to do.

If it were me, this is how I'd approach it:

1) Rip YM2203 data from sound rom
2) Interpret YM2203 data: find instruments, etc...
3) Put each sound/song into an intermediate format
4) Translate that intermediate format into something protracker can play on the Amiga hardware

Seeing those high level tasks, I believe creating a tool to do the first two jobs would be ideal... maybe the first three.

I'm a C#/Java (really anything) developer, so I can quickly create a utility app that will do those three jobs.

With the sound data in an intermediate format, it can be re-input into ProTracker format.

The reason I favor sound synthesis instead of using WAVs is that WAVs (on the Amiga, at least) take up huge amounts of room. Sound synthesis takes up relatively little, and we have the Paula chip to do it for us. (Paula, right? Not Agnes or Denise? )

Dealing with storage/loading issues will be a separate problem to solve

You ever heard of Pretracker or AmigaKlang? They can be used to pre-render samples in RAM at playtime and store the instruments as algorythms, it seems to me you want to go that way - try to get in touch with the devs and see if they can add the YM synthesis pre-rendering - because AFAIK paula can almost only play samples (albeit small) or simpler FM so that you will need to have those in RAM, chords and single samples, pre-rendered (and very likely with a better loop than the one i can set by hand)

[chadderack]

Originally Posted by saimon69

You ever heard of Pretracker or AmigaKlang? They can be used to pre-render samples in RAM at playtime and store the instruments as algorythms, it seems to me you want to go that way - try to get in touch with the devs and see if they can add the YM synthesis pre-rendering - because AFAIK paula can almost only play samples (albeit small) or simpler FM so that you will need to have those in RAM, chords and single samples, pre-rendered (and very likely with a better loop than the one i can set by hand)

Yeah that sounds about right. I remember some of this from either phx or mcgeezer's tutorial on ProTracker. I think creating short .wav samples is fine for the sampler engine... translating to the short wav samples is one of the tasks to complete. I can probably create a tool that translates from one type of sample to the ProTracker sample format and save each wavlet off as a temporary file. Then they can be imported into ProTracker. I think.

[chadderack]

Small update just to illustrate how things are going.
I don't think we need to get much further than this with the functions I'm reversing. Even a new coder could tell what this function does.

This is how I'd like to get all of the defined functions in the Ghidra project. Then we'll be ready to move forward with the port.

                             **************************************************************
                             *                          FUNCTION                          *
                             **************************************************************
                             undefined CongealBlueGoop()
             undefined         A:1            <RETURN>
                             CongealBlueGoop                                 XREF[1]:     Bank04::ad24(*)  
    Bank04::aaf4 af              XOR        A
    Bank04::aaf5 dd b6 01        OR         (IX+SPRITE_X_HI)
    Bank04::aaf8 20 12           JR         NZ,too_far_away
    Bank04::aafa 3a 02 f4        LD         A,(PLAYER_WEAPON_X_POS)
    Bank04::aafd c6 50           ADD        A,0x50
    Bank04::aaff dd 96 02        SUB        (IX+SPRITE_X_LO)
    Bank04::ab02 fe a0           CP         0xa0
    Bank04::ab04 30 06           JR         NC,too_far_away
    Bank04::ab06 21 26 ad        LD         HL,BLUE_GOOP_CONGEALS                            = 
    Bank04::ab09 c3 06 30        JP         Maybe_HandleInanimateSprites::start
                             too_far_away                                    XREF[2]:     Bank04::aaf8(j), Bank04::ab04(j)  
    Bank04::ab0c 21 1e ad        LD         HL,BLUE_GOOP_SUSPENDED                           = 
    Bank04::ab0f c3 06 30        JP         Maybe_HandleInanimateSprites::start

[chadderack]

Hey saimon69,


So for the last two days I've been reading up and gathering information on the sound stuff... ranging from PMD to MML to .M to VGM to YM2203 to AY files to HOOT, to HVR... you name it.

I've found some vgz files that someone had converted from the original source... but it was an incomplete list.

Sorry to say that the vgm format is probably too "big" for my purposes; the files tend to take up too much room. However, the original "data" seems to not take up much room at all. The Level 1 music, for instance, is only 1106 bytes long. That's fantastic; so I'd like to either eventually implement something for the Amiga that interprets the same "code" and patch data (replacing pointers, etc) the same way.

I'd like to be able to find a standalone player that will play the music data "as is" from the sound rom itself. If the code to do that was open source--so much the better!

Following instructions from this page (and related), I was able to make HOOT load up a test .M file and play it. It was the level 1 music data from Black Tiger.

Unfortunately I don't understand the .M file spec, which means I'm probably not putting all the data in the correct spots... and the tune plays back at a really low pitch. I'm guessing that I need patches defined somewhere in the .M file. If you or someone you know has the .M (OPN) file spec and could share that with me, that would be great.

I would love to simply be able to find all of the needed data to play a song or sound and hand-edit a binary .m file to create a proper .m file. Or if there's a tool that does that, so much the better


...

In general news, the reversing continues. I'm to the point where pretty much all the sprite data has been tagged with fairly accurate names... and many more functions have been named much better. Certain parts of the game code are really starting to resemble more English than gibberish.

I'm starting to see how the animation frames for a character are interleaved with decision points, where the code will run a function (pointer) for each character during an animation sequence. Based on what happens in the function, it can either loop back to the beginning of an animation sequence, or switch. If the sequence switches, you'll notice in code that the animation "bookmark" (or the pointer to the current animation frame byte) will move forward past the next few bytes.

;pseudo z80 code

INC HL
INC HL
INC HL

So the character animation is less like real "AI" and more like a "scripted" AI, which has decision points every few frames.

[chadderack]

ETA: Just found this, and it looks pretty good.

https://gitlab.com/bunnylin/supersak...er/doc/pmd.txt

If anyone (in the meantime) has better information about the .m file format (specifically) please let me know. Thanks!